CELL BIOLOGY AND CELL IMAGING CORE A. DEFINITION The Cell Biology and Cell Imaging Core is a new Core that has evolved from aspects of two previous cores, the Cell Biology Core which focused on live cell imaging, and the Histochemistry/Morphology Core which focused on cell structure and the localization of biological molecules in fixed cells. The Cell Imaging Core is designed to provide information on the localization of molecules in live and fixed cells and their changes over time and in response to physiological and pathophysiological perturbation. It is centered around microscopic imaging and quantitative analysis of digital information obtained primarily by last scanning confocal microscopy (LSCM) and multiwavelength fluorescence imaging although traditional electron microscopy of fixed and embedded specimens is also available for fine structure analysis. Modern biomedical research is characterized both by its interdisciplinary nature and by its dependence on increasingly sophisticated instrumentation. While much of the research carried out by GI Center investigators involves cellular and molecular biological techniques, the interpretation of these data often has to be put in a spatial context. Cells are not just featureless bags of enzymes and proteins and many tissues regulated by hormones and/or affected by disease are highly structured such as epithelial cells and neurons. Modern morphologic techniques provide understanding of changes in cell structure and information on sub cellular localization of specific proteins. This latter function usually involves immunolocalization and has been greatly facilitated by the techniques of fluorescent LSCM. Moreover, more investigators are combining molecular biology and structural biology by engineering epitope tags onto their proteins expressed by transfection with cDNA. This is being extended to the living cell level using green fluorescent protein (GFP) chimeric proteins creating a fluorescent protein which can be visualized in a living cell and whose translocation can be followed between cellular compartments. Protein-Protein interaction in living cells can be studied using FRET, which in its most common form will use variants of cyan and yellow fluorescent protein (CFP and YFP) tagged proteins. The new Cell Biology and Imaging Core is built around sharing resources with the Morphology and Image Analysis Core (MIAC) of the Michigan Diabetes Research and Training Center (MDRTC). This arrangement is facilitated by the fact that Drs. John Williams and Stephen Ernst direct both the MIAC and the new GI Center Cell Imaging Core. This arrangement will allow GI Center investigators to obtain access to more equipment and at a reduced recharge rates. This evolution also involves a shift to a more service-oriented center with recharge fees, which were not charged previously in the GI Center. The support of the GI Center will allow the maintenance and oversight of Core equipment, which is outgrowing the ability of the MDRTC to provide. Because the MIAC does not include an electron microscope, EM analysis will utilize an instrument housed in the Morphology and Image Analysis Laboratory (MIL) of the Cell and Developmental Biology Department. While the Cell Imaging Core will make use of the available highly sophisticated instrumentation, it also is built around the over 60 years of combined cell biology and imaging expertise of Drs. Williams and Ernst which has been primarily devoted to GI Tissues. They will be available to assist Center Investigators with experimental design and interpretation of data. Core personnel, particularly Dr Lentz and Mr. Nelson, will demonstrate and teach techniques to GI Center investigators, trainees and technicians. Finally another mission of the Core is to initiate, implement and disseminate new and innovative imaging techniques. As a result of the reorganization of this Core, several previous functions of the prior Cell Biology Core including electrophysiology and production of canine gastric mucosal cells has now been shifted to the In Vivo Studies Core. We have also dropped as a service FACS analysis as there is a University Core in the Cancer Center which provides excellent service which GI Center members are currently using at a modest cost.